Allergic conditions in the past have been treated with a variety of drugs including those characterized as 1-alkyl-4-(5H-dibenzo[a,d]cyclohepten-5-ylidene)-piperidines.
Prior to the present invention, it was known that the compound cyproheptadiene of the structure ##SPC1##
Was an active antihistaminic and antiserotonin agent and was therefore useful in the treatment or relief of certain allergic conditions. This is disclosed in U.S. Pat. No. 3,014,911, Edward L. Engelhardt, which patent was issued Dec. 26, 1961.
The novel 1, 2 or 3-carboxy compounds of the present invention are distinguished from the prior art patented compounds by their ability to stimulate appetite in underweight or undernourished patients without the concommitant side effects present in other cyproheptadine analogs, such as anti-cholinergic activity. In standard laboratory animals, the compounds of the present invention are found to have appetite stimulant activity.